The greatest antibacterial activity showed the preparation obtained from Lactobacillus plantarum after 48 h of culturing in MRS medium with glucose. The antibacterial preparation limited growth of Yersinia enterocolitica by five orders of magnitude (to 10³ cfu/mL) after 24 h of incubation with the preparation, as compared to the control sample with the cell number of 10⁸ cfu/mL.